Lever-latching device



LEVER LATGHING DEVI CE Filed July 25 1928 gwuento'c l the points of the latter Patented Mar. 24, 1931 LARKIN a. snare Lava-smart:

Application and July 2-5,

This invention relates to improvements in locking or latching niechanlsms for levers, and particularly to a latching mechanism for the operating levers of what are commonly 5 known as groundthrow switches or stands. One of the objects ofthepresent invention is to provide a novel form of lever latch-or keeper, and particularly a latch ior the op erating lever of a railway'switch, the preferred' arrangement beingsuch as to permit the switch operating mechanism,including the switch operating lever, to operate automatically under force created'by flanges of car wheels running through the switch when are not properly alined. This automatic release feature prevents damage to the operating mechanism under abnormal conditions, such asoutlined.

\Vith these and other" objects inview, the

invention consists in certain novel details of construction and combinations and arrangements of parts, all as will hereinafterbe more fully described and the novel features thereof particularly pointed out inthe appended In the accompanying drawings: Figure 1 is an elevational viewofa latch or keeper adapted for use with a ground throw switch .stand, the lever latching arm 30 for the operating lever being "shown in fully lever 11, shown in cross section in Fig; 2.v

Slot 10 is formed between two upright extensions, these extensions, for convenience, being termed a standard 12 and a guide post 13.

When the switch operating lever 11 is to be locked in the slot 10, a latch arm 14 is adapted to span said slot at a point above lever 11, said lever lying on the bottom of the slot when in locked position. Preferably, latch arm 14 is pivoted on a pivot pin 21 in s or semiannn rnn :rne nnvron 1328. Serial no. 295,2;2.

one'of'sa-id'stand extensions, guide post 13, in the present instance, and its free end projects laterally beyond standard 12, as shown in 2, when the, arm is in lever'locking position; For holding latch arm 14 in locking position, and thereby holding the switch safe under ordinary trafi'ic conditions, the free end 01 said arm has pivoted thereto, a weight 15 that is, movable by. gravity to assume a position beneath a projection'lG on ste card 12 when the arm is in locking positiion. Weight 15 is pivoted eccentrically on arm- 14 andnpon excessive strains on lever 11, as when the flanges of car'wheels run through a switch that is not properlylined up,'arm 1d is slightly raised and weight 15 brought into engagement with projection 16, with the resnlt'that said weight is par-'1 tially rotated on its pivot until it assumes a position'wliere it. is free to ride from said projection. In this way, the operating lever 11 is releasably or yieldingly 'held' in its locked position, and when abnormal conditions exist, as just outlined, arm 14 is free to raise, so that breakage or bending or other resulting damageof the stand and switch operating vconnections is prevented;

' In order that thelatch arm1l; will assume its locking position whenever operating 'le-j ver 11 is moved down into slot 10, said arm has an eXt-ensionornose portion 17 formed thereon, which is movable" into slot 10 when arm 14 is caused to assume its fully unlocked position, as shown 'in Fi ure'l; Nith nose 1'? thus locked in slot 10, as lever 11 is lowered into slot 10, arm 14 will be turned on its pivot and after it has passed its pivotalcenter, weight 15 will cause it to flop'over, so to speak, and assume its 'lockedposition. V

In normaloperation, latch 'arm'le maybe moved from locked to nn lo'cked position by means or" a foot pedal 18 carried on asecond extensionlQ ofsaidilatch arm. Nose 17 of the latch arm mayialso be. provided, with an aperture or eye 20, for the usual'switch lock.

Iclaim: 1.---ln a .lever; latching device, the combination of'a standard, a guide postspaced forming a lever receiving movable to lever locking position across said slot, and cooperating elements on said standard and arm for yieldingly locking said arm in said slot.

2. In a lever latching device, the combination of two upright extensions having a lever receiving slot between them, a latch arm pivoted on one of said extensions and havinga free end adapted to project laterally beyond the other extension when. in lever locking position, and means carried by said arm and engageable with said other extension for holding said arm in lever locking position.

3. In a lever latching device, the combination of two upright extensions having a lever receiving slot between them, a latch arm pivoted on one of said extensions and having a free end adapted to project laterally beyond the other extension when in lever locking position, and means carried by said arm and en- 1 gageable with said other extension for hold- 1ng sald arm 1n lever locking positlon, said holdlng means yieldingly engaging said other extenslon.

4. In a lever latching device, the combination of two upright extensions having a lever recelv lng slot between them, a. latch arm pivoted on one of said extensions and having a free end adapted to project laterally beyond the other extension when in lever locking position, and means carried by said arm and engageable with said other extension for holding said arm in lever locking position, said holding means comprising a projection on said other extension and a swingable weight carried by said arm movable by gravity to a position beneath said projection when the arm assumes its lever locking position.

5. In a lever latching device, the combination of two upright extensions having a lever receiving slot between them, a latch arm pivoted on one otsaid extensions and having a free end adapted to project laterally beyond the other extension when in lever locking position, and means carried by said arm and engageable with said other extension for holding said arm in lever locking position, said holding means comprising a projection on said other extension and a weight eccentrically pivoted on the latch arm and movable by gravity to a position beneath said projection when said arm assumes its locking position.

6. In a lever latching device, the combination of two upright extensions having a lever receiving slot between them, a latch arm pivoted on one of said extensions and having a'free end adapted to' project laterally beyond the other extension when in lever locking position, and means carried by said arm and engageable with said other extension for holding said arm' in lever locking position, said holding means comprising a projection on said other extension and a swingable weight carried by said arm movable by gravity to a position beneath said projection when the arm assumes its lever locking position, said weight being movable by said projection to release said arm and lever.

7. In a lever latching device, the combination of two upright extensions having a lever receiving slot between them, a latch arm pivoted on one of said extensions and having a free end adapted to project laterally beyond the other extension when in lever locking position, and means carried by said arm and engageable with said other extension for holding said arm in lever locking position, said holding means comprising a projection on said other extension and a weight eccentrically pivoted on the latcharm and movable by gravity to a position beneath said projection when said arm assumes its locking position, said weight being movable on its pivot by said projection to release said arm and lever.

8. In a lever latching'device, the combination of two upright extensions, there being a lever receiving slot between said extensions, a latch arm pivoted on one extension adapted to bridge said slot when in locked position, a projection formed integrally with said arm movable into said slot when the arm is in unlocked position, and a foot pedal formed integrally with said arm and its extension.

9. In a lever latching device having a lever receiving slot with upright extensionsat opposite sides thereof, alatch arm pivoted on one extension adapted to bridge said slot. and project laterally beyond the other extension when the arm is in locking position, and means for yieldingly holding said arm in looking position, said means comprising a weight movable to one side of the pivotal center of said arm when the latter is in unlocked position and movable to the opposite side of said center when the arm is in locked position.

LARKIN N. SI-IAFFER. 

